Elastic constants of the bcc phase in niobium-zirconium alloys between 4.2 and 300 K

The adiabatic elastic constants have been determined for quenched single crystals of niobium-zirconium alloys of the following nominal compositions: 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 70 at.% Zr. The c11, c12, and c44 constants as well as the shear constant C′= (1/2) (c11−c12) and the bulk modulus are given between 4.2 and 300 K. We observe for the whole range of compositions an anomalous temperature behavior for c44 similar to that found in pure Nb, but here the amplitude of the effect disappears progressively with increasing Zr concentration. The Debye temperatures were computed from the constants at 4.2 K.